Tertiai^j Fossils. 23^3 



Fam. ASTRAEIDAE. 

 Genus Monti ivaltia, Lamaroux. 



cf. Montliraltia, sp. 

 A species with a large discoidal, depressed calyx. 

 Cudinore Collection. 



Genus Orb ice I la, Dana. 



Orbicella tasmaniensiif, Duncan sp. Plate I. Fig. 1. 



IleUastraea faamanie/isis, Duncan, 1876, Quart. Journ. Geol. 

 Soc. vol. XXXII. p. 342,, pi. XXII., Figs. 1-3. 



Astrangia tahiilosa, Tate, 1893, Journ. R. Soc. N. S. Wales, voL 

 XXVII. p. 145, pi. XIII. Fig. 2. 



Two species of the above named coral were presented by Dr. 

 Griffith Taylor. They occur in the hard, reddish limestone of the 

 Tertiary series, and were found on the surface of a salt lake east 

 of Ooldea. One of them is preserved in hard, semi-crystalline 

 limestone, in which the coral structure is much obscured; whilst 

 the other is weathered and whitened, so that it has the appearance 

 of a living coral. The structure of the weathered specimen is, how- 

 ever, none the less perfect, for this process has simply picked out 

 the calcareous infilling. A large numl)er of wind-worn pieces of 

 this coral was also secured by Mr. Cudmore, who states that they 

 occur scattered over the limestone plains. By their blackened and 

 polished surfaces the fragments appear to have Ijeen exposed to 

 the weather for a long time. 



The species, living and fossil, formerly referred to the genus 

 IleUastraea, are now lelegated to Orbicella by Verrill and Quelch~ 

 by reason of priority. 



There is a close agreement of these specimens from Ooldea with 

 those from Tasmania, thougli the former have the calices rather 

 larger in diameter (i) iS). Tlie weathered specimen shows tliat, 

 although the dissepiments are, asi a rule, curved downwards, this is 

 by no means invariable. This specimen has the mesenteric pouches 

 filled with a pale glauconite, thus showing, in common with other 

 organic marine bodies, a tendency for the body cavity to act as a 

 receptacle for the deposition of tlic hydrous silicate of iron, alumina 

 and potasli to form that mineral. 



Orbicella tasmaniensis has, up to the present, l)een unknown 

 from any locality outside Tasmania, e.Yccptintr FUMiiingtoii, Victoria. 



Taylor and Cudmorc Collections. 



2. Rep. Chall., Vol. XVI.. Zool. 1886, p. 106. 



